When extending the standard GUI functionality, using either a manually
installed local/share/check_mk/web plugin or a Check_MK extension
package (MKP), exceptions may occur while loading the plugin.

In previous versions these exceptions caused the whole GUI to fail making it
impossible to repair the problem using the GUI, for example via the extension
package manager of the CEE/CME.

The extension related loading errors are now all catched and logged to the
var/log/web.log instead of making the whole application fail. In
addition to this, an error message will be shown on the "Extension packages"
WATO page. We've also added a new Analyze configuration check "Broken GUI
extensions" which will report a CRIT state when broken GUI extensions are
found.